If your DH is still having that much pain he likely needs better pain management through medication or other medical procedures. If the nerve is inflamed, there are injections that can be done to help that come around much faster. These are usually done by specialists and should be done with a flouroscope (kinda like a live video x-ray) to make sure the injected medication makes it to the target tissue. There are also medications that help with nerve pain much better than the standard Vicodin, Codeine etc. Here, I would refer people to our local pain management clinic, you might have to talk to your family MD or neurosurgeon about this and to get a referral. I'm not saying that all his pain is coming from nerve pain. I'm just trying to give you some examples and reasons why you should be discussing other non-surgical options with the Doc.
PT is very helpful for learning positions to avoid, activities to avoid and starting up with exercises in a nice graded and safe manner.
As for how long and when is it safe to do certain activities... that is very individual and is another really good reason why he should be going to a PT or being monitored regularly by a Doc. There really is no way to answer that question except with the help of a professional that has one on one time with your DH.
The longer he is in a lot of pain and not funcitoning normally, the longer it will take him to recover so I would strongly recommend you look into these things sooner rather than later.
The majority of back injuries will recover and he should be able to return to cycling. But 2 months is too long for him to be putting up with that kind of pain and activity restriction.
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